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%I #9 Oct 17 2019 16:39:32
%S 378,1068,24390,29220,32118,56130,70620,74760,77658,82350,96978,
%T 100980,110640,114228,132858,152040,177018,183090,186678,214830,
%U 253608,282588,290040,319158,342480,345378,374358,388710,406788,418380,428040,442530,463230,463920,477720
%N Values of m such that N = (am+1)(bm+1)(cm+1) is a 3-Carmichael number (A087788), where a,b,c = 1,2,69.
%H Amiram Eldar, <a href="/A065702/b065702.txt">Table of n, a(n) for n = 1..10000</a>
%F am+1, bm+1, cm+1 are primes and am|(N-1), bm|(N-1), cm|(N-1).
%t CarmichaelNbrQ[n_] := ! PrimeQ@ n && Mod[n, CarmichaelLambda@ n] == 1; Select[ Range@ 500000, PrimeQ[# + 1] && PrimeQ[2# + 1] && PrimeQ[69# + 1] && CarmichaelNbrQ[(# + 1)(2# + 1)(69# + 1)] &] (* _Robert G. Wilson v_, Aug 23 2012 *)
%Y Cf. A064238-A064262, A065695-A065703, A087788.
%K nonn
%O 1,1
%A Harvey Dubner (harvey(AT)dubner.com), Nov 14 2001